The present invention relates in general to a pulse rate monitor and, in particular, to a monitoring device which provides for the concurrent analysis and display of pulse rate and variations thereof.
Monitoring devices of this kind are known in the art. One of such devices is disclosed in my U.S. Pat. No. 4,489,731 and designed such that it can be worn by a user. This device employs a histogram unit displaying the distribution of time intervals between successive heart beats of a user, and also measures and displays an average frequency of the heart beats. The prior art monitor, however, determines the histogram of time interval distributions without regard to outside factors affecting the user, particularly without regard to the magnitude and change in the time of physical load applied to the user. The applied load or actions performed by the user can be measured for example, by the number of paces of a walking person, by a number of revolutions of bicycle pedals or wheels, by the number of particular movements of an exerciser and the like.
SUMMARY OF THE INVENTION
It is therefore a general object of the present invention to provide a pulse rate monitor which avoids the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a pulse rate monitor by means of which it is possible to determine the frequency of heart beats of a user as a function of frequency of physical actions performed by the user irrespective of changes in frequency of such actions (for example, regardless of the frequency of paces of a walking person); as a function of a total number of individual actions performed by a user (expressed for example, as a total number of paces, a total number of bicycle revolutions etc., counted from the beginning of the measurement; and as a function of the duration of physical actions or loads expressed for example, as a total elapsed time of walking, exercising, etc.
In keeping with these objects and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in a combination which comprises a first detector for a first sequence of pulses; an electronic histogram unit having an input and a plurality of output channels corresponding to predetermined pulse spacings; a set of first counters and a set of second counters each having a data input and a plurality of data outputs and each being provided with with display means, the first and second counters being assigned to respective output channels of the histogram unit; a set of dividers connected between the outputs of the first and second counters to produce quotients of counts of the latter, each of the dividers being provided with display means; a clock pulse generator; a second detector for a second sequence of pulses; switching means having a first switching position in which the first detector is connected to the input of the histogram unit, the inputs of the first counters are connected, respectively, to the output channels and the second counters being connected in series with the averaging unit, and a second switching position in which the first detector is connected to each input of said first counters, said second detector is connected to the input of said histogram unit, and the inputs of said second counters are connected to an output of said clock pulse generator; and control means for controlling the connection between said first detector to said first counters and the connection between said clock pulse generator and said second counters to activate, in the second position of said switching means, those first and second counters which pertain to an active output channel of said histogram unit.
The novel features of the present invention are set forth in particular in the appended claims. The invention itself, however, will be best understood from the following description of a prefferred embodiment when read in connection with the accompanying drawings.